12 de junio de 2008

GTH parte II.

Para el ejercicio 3 habia que saber algo de redes, como se rutean mensajes entre computadoras, y no mirar el grafo! El ejercicio 4 era el que tenia base matematica, igual no mucha. Habia que buscar varias secuencias de numeros primos consecutivos cuya suma tambien sea primo. Era mucho mas facil de lo que me habia imaginado al principio. Una posible solucion es crear una tabla de primos grande (107 por ejemplo), y luego poner las condiciones mas fuertes primero, y luego las mas debiles.

9 de junio de 2008

Sayonara Kubuntu.

Until last year I was a happy Kubuntu user. I started as an occasional user with HoaryHedgehog and Dapper Drake, first with the normal Gnome version later switching to KDE. Almost two years ago with the release of Edgy Eft I've switched my main desktop to Kubuntu, I remember this version was a bit sloppy, because it was a rushed version with only 4 months of development, but in general was a good release.

The same goes for the next versions, but unfortunately they keep releasing sloppy versions. A change here, a change there, and little bits of pieces were broken, really nothing too serious, but when you take a look from a distance you find that you have to solve same problems over and over again, and it start to look ridiculous. All started with this bug report Can't init Maxima session withing TeXmacs, to have a better startup times Ubuntu have switched the defaul shell from Bash to Dash, these change broke a large number of scripts that relly on the assumption that sh=bash. These bug report have a workaround, it is not elegant but works, but in the three versions since them (Feisty, Gutsy and Hardy), the packages are broken. I can live with these, it's annoying, but since I use my box mostly to develop, I've to make the change so sh points to bash, or else a lot of configure scripts don't work as expected.

But the worst bug is this DDC report some ridiculous physical screen size, but it was reported previously as Large font in Gdm login text and the oldest related report I can find of Gdm login text field shows overly large characters. In Gnome the only affected is Gdm, if you can correctly type your username and password you get the desktop and everything is normal. But in KDE the whole desktop is a mess and you really can't work, one ugly workaround is adding a line Option "DDC" "False" in your xorg.conf. These bug was not fixed in Gutsy, but the intel driver was optional and you can have it installed alongside the old i810 driver. But the default driver in Hardy is now intel.

Another fault of Gutsy was that it included D3lphin as default filemanager instead of Konqueror. It is a good filemanager but the KDE 3 version is no longer supported, because most of the resources were focused in the KDE 4 release. So d3lphin was a spinoff while KDE4 was not released, and huge problem for me was that it didn't support # in filenames or folders, the fix mentioned in the forums was to rename such folders. But I can't rename filenames inside a CDR!

Here is another problem with Ubuntu, once a final version is released the packages are frozen, no more updated versions, only critical and security bugfixes. If you want a new version you have to request a backport and wait if a developer is interested enough, or compile your own version (which I think is the fastest way). But I know that some packages are allowed to break this rule, ie Firefox. Other problem is that between versions you have to do a full upgrade and can't do a partial upgrade. Well if you are lucky enough you can upgrade a simple package if it doesn't have a complex set of dependencies, but you have to install it manually.

I know Ubuntu is moslty done by volunteers, I've talked to several of them in the IRC channels, they are passionate, dedicated and good persons. You can't blame them, they work really hard, just a Linux distribution like Ubuntu require a lots of people to work together to make a release, and they are not enough. Perhaps Ubuntu is a victim of it own success, having a large user base also implies there are a large number of bugs reported, this in turn requires a better organization as a whole, a more formal QA process and more involvement from Canonical.

8 de junio de 2008

Cine: Los crimenes de Oxford.

Hace algún tiempo comentaba sobre el libro Crímenes imperceptibles de Guillermo Martínez, el libro tiene un par de vueltas interesantes, mezcla de género policial con algo de matemáticas (a veces demasiada), y si les gusta el género policial resulta una lectura recomendable, pero si les gusta la matemática hay partes que no les va a gustar. Luego me enteré de que se estaba planeando una película sobre el libro, y que iba a ser dirigida nada más y nada menos que por Alex de la Iglesia, todo presagiaba una buena película. Bueno ahora que vi la película mi conclusión es que deja bastante que desear. Hay muchos cambios respecto a la historia del libro:
  • El protagonista principal es norteamericano y se llama Martin, en el libro es argentino y se llama Guillermo.
  • La introducción de los personajes es bastante apresurada y parece forzada, en el libro es más casual.
  • El personaje de Beth tiene una actitud activa y decidida, en el libro es más sumisa y se deja llevar por las circunstancias.
  • El protagonista juegan squash, en el libro en cambio juega tenis.
  • Cuando Seldom esta dando su clase, el contenido del pizarrón no coincide con el tema.
  • El protagonista llega a Oxford y no tiene director, en el libro cuando llega si tiene una directora de tesis.
Y así hay cambios a lo largo de toda la película que no los pongo por si les interesa verla. No me gustan los juego de palabras pero en este caso la película es un crimen (de buen gusto) bastante perceptible.